Quaternary organophosphonium halides and preparation thereof



United States Patent Office 3,333,005 Patented July 25, 1967 3 333 005 QUATERNARY onoAisoi riosrrroNrUM HALIDES AND PREPARATION THEREOF Martin Grayson, Norwalk, Patricia Tarpey Keough,

Ridgefield, and Michael M. Rauhut, Norwalk, Conn.,

assignors to American Cyanamid Company, Stamford,

Conn., a corporation of Maine No Drawing. Filed June 4, 1963, Ser. No. 285,223

8 Claims. (Cl. 260-6065) The present invention relates to organophosphorus compounds and to a method of preparing same. More particularly, the instant discovery concerns phosphonium salt derivatives of tertiary phosphines.

It has been found that tertiary phosphines generally will react with halo-substituted ethanol to produce the corresponding trialkyl-, tricycloalkyl-, or triaryl- 2- hydroxyethylphosphonium salts. In turn, these salts may be acylated using a lower alkanoic anhydride, lower alkanoic acid, or the like, to produce their corresponding trialkyltricycloalkyl, or triaryl- Z-acetoxyethylphosphonium salts.

The following equations illustrate this general reaction:

GB 9 R R R P XCHaOHzOH R R R PCHacHzofi-X agent R R R each representing, as will be seen hereinafter, alkyl, cycloalkyl and aryl, X representing halogen or tetraphenyl borate, and Y representing the residue of an acylating or esterfying agent. The following is a typical embodiment of generic equations (A) and (B) above;

6D I G (n-C4H );PCHzCHzOCH -Br The trialkyl-, tricycloalkyl-, and triaryl- Z-acetoxyethylphosphonium salts prepared as above may, in turn, be converted to their corresponding vinylphosphonium salts according to the following general equation:

GB 9 base as 9 O)R R R POH,OH,0YX R R R PCH=CH X in which R R R", Y and X are the same as above.

The following is a typical embodiment of equation (C), above:

More specifically, in generic equations (A), (B) and (C), above R R and R each represent alkyl C -C substituted alkyl C C cycloalkyl, and aryl; X represents halogen, such as brorno, chloro and iodo, and tetraphenyl borate; and Y in equations (B) and (C) represents the residue of an acylating agent as shown in the specific embodiments, supra.

Typical tertiary phosphine reactants are the following:

tri-methylphosphine, triethylphosphine, tripropylphosphine, tributylphosphine, tripentylphosphine, trihexylphosphine, triheptylphosphine, trioctylphosphine, trinonylphosphine, tridecylphosphine, tr-iundecylphosphine, tridodecylphosphine,

tritridecylphosphine, tritetradecylphosphine, tripentadecylphosphine, trihexadecylphosphine, dodecyldiethylphosphine, dioctylpropylphosphine, diethylbutylphosphine, butylethylhexylphosphine,

tri( Z-meththoxypentyl) phosphine, tris-2-cyanoethylphosphine,

die thyl-2-ethoxyheptylphosphine, tricyclopropylphosphine, tricyclohexylphosphine, triphenylphosphine, diphenylnaphthylphosphine, trixylylphosphine, tritolylphosphine,

tris paraethoxyphenyl) phosphine, tris (para-chlorophenyl) phosphine, tris (Z-chlorophenyl) phosphine, tris (3 -bromophenyl phosphine, and the like.

Typical esterifying agents follow: lower alkanoic anhydrides, such as acetic anhydride, propionic anhydride, butanoic anhydride; lower alkanoic acids, such as formic acid, acetic acid, propionic acid, butanoic acid; acylating (C -C alkanoyl) halides, such as acetyl chloride, propionyl bromide, butyryl iodide, octanoyl chloride, dodecanoyl bromide, stearyl chloride, hexanoyl bromide; isopropenyl acetate; aryl sulfonyl halides, such as para-toluenesulfonyl chloride, phenyl sulfonyl bromide, 2,4-dimethylphenylsulfonyl chloride; alkyl (lower) chloroformates, such as ethylchloroformate, butylchloroformate; alkyl (lower) carbonates, such as diethylcarbonate, dipropylcarbonate, dibutylcarbonate; ketene; dirnethyl sulfate; nitrosyl chloride; and trimethyl phosphate.

In equation (C), above, typical suitable inorganic and organic bases are: alkali metal hydroxides, such as sodium hydroxide, potassium hydroxide, lithium hydroxide; alkali metal carbonates, such as sodium carbonate, potassium carbonate, lithium carbonate; alkaline earth metal hydroxides, such as magnesium hydroxide, barium hydroxide, calcium, hydroxide; alkaline, earth metal carbonates, such as magnesium carbonate, barium carbonate, calcium carbonate; activated alumina; and quaternary ammonium hydroxides, such as tetraalkyl (lower) ammonium hydroxides, including tetramethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabenzylammonium hydroxide; and basic ion exchange resins.*

The reaction in equation (A) hereinabove is carried out at a temperature in the range of 30 C. to 250 C., preferably 60 C. to 180 C. The equation (B) reaction, above, is best carried out at a temperature in the range of 5 C. to C. As to equation (C), above, this reaction is generally carried out at a temperature in the range of 20 C. to 0., preferably 50 C. to 150 C.

Each of these three reactions may be carried out at atmospheric, sub-atmospheric or super-atmospheric pressure; preferably, however, reaction is carried out at atmospheric pressure. By the same token, the ratio of the re- Typical are: polymeric quaternary ammonium salts, e.g,, polymeric trimethylbenzyl ammonium chloride, etc.

out in the presence of an inert organic solvent, i.e., a solvent which does not enter into or otherwise interfere with the reaction under the conditions contemplated herein. Typical solvents are dimethoxyethane, dioxane, ethylacetate, tetrahydrofuran, and the like.

The reactions of equation (B) similarly are best carried out in the presence of an inert organic solvent of the type described for equation (A), as well as acetic acid, dimethylformamide, digly-me, and the like.

As to equation (C), typical suitable inert organic solvents in which the phosphonium salt is solvent, which solvents do not interfere or enter into reaction to any substantial degree, are dimethoxyethane, dioxane, dimethylformamide, diglyme, acetonitrile, ethylacetate, tetrahydrofuran, and other like linear and cyclic ethers, acetate esters (lower alkyl).

Alternatively, it has been found pursuant to the instant discovery that the products of equation (A), above, may be converted directly to the products of equation y.

69 G 69 9 RIRYR3PCHZCHZOHX RIRQR3PCH=CHZX in the presence of any base given above for equation (C) and at a temperature in the range of 100 C. to 250 C. As in equation (C), a solvent of the type given hereinabove for equation (C) is suitable and herein contemplated. If desired, the reaction may be carried out in the presence of a dehydrating agent, such as a siliceous agent including silica (e.g. silica gel), silica-alumina, and the like, in which other inert organic solvents are also suitable, e.g. aromatic hydrocarbons, such as toluene, benzene, xylene, cymene, and the like, methylene chloride, ethylene chloride, etc.

The products of equations (A), (B), (C) and (D) above are useful as fire retardants in plastics, e.g., from 0.5 to 30 parts by weight of any one of above compounds when incorporated into 100 parts by weight of a thermoplastic polymer material, such as polyethylene, polypro pylene, polystyrene, polyacrylate, polymethylmethacrylate, or the like, provides enhanced fire retardance to the polymer material upon exposure to an open flame.

While the following examples specify certain details as to certain embodiments of the present invention, it is not intended that these details impose unnecessary limitations upon the scope of the instant discovery, excepting of course that these limitations appear in the appended claims:

EXAMPLE I T ributyI-Z-hydroxyethylphosphonium tetraphenylborate Tributyl 2 hydroxyethylphosphonium bromide, obtained from combining tributylphosphine and 2-bromoethanol in 1,2-dimethoxyethane and refluxing under nitrogen, is dissolved in water and treated with excess 01 N sodium tetraphenylboron. The resulting precipitate is filtered and recrystallized from ethanol to yield product tributyl-2 hydroxyethylphosphonium tetraphenylborate with melting point 124 C.-125 C. Analysis of product (Found: C, 80.03; H, 9.00; P, 5.35. C H O requires: C, 80.55; H, 9.25; P, 5.47%.)

As is evident from this example, the halide salts of equation (A) may be converted, in situ or after recovery thereof, to the corresponding tetraphenylborate salts.

EXAMPLE II Tributyl-Z-acetoxyethylphospholzium bromide 1,2-dimethoxyethane (275 milliliters), freshly distilled from calcium hydride, 2-bromoethanol (133 grams, 1.06 moles), and tributylphosphine (204 grams, 1.01 moles) are combined under nitrogen and refluxed at 85 C. overnight with stirring. A heavy oil forms within an hour. Isopropenyl acetate (320 grams, 3.2 moles) and 48% HBr (3 drops) are slowly added to the reaction mixture which is then refluxed 18 hours. Volatile components are removed in vacuo at 70 C. Product (372.5 grams;

99.9% yield) remains as a thick hydroscopic oil, which could be forced to crystallize by stirring in a benzene petroleum ether (boiling point 30 C.60 C.) mixture. Crystalline tributyl-Z-acetoxyethylphosphonium salt is obtained from part of the oily produced by freeze drying a benzene solution of the oil.

EXAMPLE III Tributyl-Z-acetoxyethylphosphonizmz tetraphenylborate Tributyl-2-acetoxyethylphosphonium bromide oil (16.2 grams produced as in Example II, above) is dissolved in water and treated with sodium tetraphenylboron (15 grams) dissolved in water. A white precipitate appears which is filtered and recrystallized from ethanol containing enough acetonitrile to cause solution at the boiling point of the mixture. Tributyl-2-acetoxyethylphosphonium tetraphenylborate (16.7 grams) is obtained with melting point of 177 C.179 C. Analysis of product (Found: C, 76.65; H, 8.83; P, 5.24. C H O BP requires: C, 78.93; H, 8.94; P, 5.10%.)

EXAMPLE IV T riphenyl-Z-acetoxyethylphosphonium iodide 2-iodoethyl acetate is prepared from the nucleophilic exchange reaction of sodium iodide and 2-ch1oroethylacetate in refluxing acetone under nitrogen (boiling point 86 C.90 C. at 33 milliliters mercury). Triphenylphosphine (7.35 grams) is reacted with 2-iodoethylacetate (24 grams) under nitrogen with stirring at 80 C. for 4.5 hours. The excess 2-iodoethylacetate is distilled ofl in vacuo. Crude, brown crystalline product (14.20 grams) is obtained by washing oily residue with ether. It is washed with ether, ethylacetate, and acetone and recrysstallized from acetonitrile to give prod-uct (7.90 grams) with melting point 161 C.-163 C. Analysis of product (Found: C, 55.16; H, 4.80; I, 26.77; P, 6.45. C H O IP requires: C, 55.47; H, 4.66; I, 26.66; P, 6.51%.)

Example IV represents still another embodiment of the present invention wherein the product salts of equation (B), above, are prepared directly from the reaction of a 2-haloethy1 acetate with a tertiary phosphine of the type contemplated herein.

The process of Example IV, above, may be carried out using any of the tertiary phosphine reactants contemplated herein and the corresponding tri-substituted -2- acetoxyethylphosphonium halide produced and recovered, according to the following equation o RIRZRQP xoH omoii-oH R R R %GH CH;OY%

wherein R R R X and Y have the meanings given hereinabove in equations (A) and (B).

Equation (E) is best carried out at a temperature in the range of 5 C. to 0., preferably at the reflux temperature 0 fthe solvent employed. Typical inert organic solvents contemplated for equation (E) are acetone, lower alkanol (ethanol, butanol), plus the solvents listed hereinabove for equation (C). The reaction under equation (E), as shown in Example IV, supra, is best carried out under inert conditions, such as under nitrogen. Other 2-haloethyl acetate reactants contemplated herein are 2-bromoethyl acetate and 2-chloroethyl acetate.

Tables A, B, C, D and E, which follow, correspond to equations (A), (B), (C), (D) and (E), respectively. The examples in Tables A and B are carried out essentially as in Examples I and II, respectively supra, excepting of course as shown in Tables A and B. The examples in Table C are carried out essentially as in Example LX, infra, excepting of course as shown in Table C. Likewise, the products of Table D are recovered essentially as in Example LX, infra. The examples in Table E are carried out essentially as in Example IV, supra, excepting of course as shown in Table E.

TABLE B Example Product of GB Moles 9 Moles Solve milli- No. Example R3PCH2CH2OH'X A A liters (ml.) 0. Product XII V 1. Isopropenyl acetate- 3. 2 DME, 300 ml 83 Z-zcetorrgethyltrimethyl phosphonlum roml e.

XXIII"..- VI 1. 0 Dimethyl sulfate.-- 3. 8 Dioxane, 300 ml... 90 Z-methylsulfatocthyltributylphosphonium chloriie. XXIV. VII 0. 8 Acetic anhydridel. 0 Acetic acid, 300 ml. 120 2-ac1e1toiggethyltributylphosphonium c on e.

XXV VIII 0.9 Nitrosyl chloride 1. 1 Digly'me 120 2-hiigofthyltributylphosphonium XXVI. IX 1. 0 Acetyl chloride. 1. 2 DME, 500 ml 3O Z-agaetorrgethyltriisobutylphosphouium XXVII XI 1. 0 p-Toluenesulfonyl 1. 0 DME, 200 ml 60 2-(p-toluencsulfonyloxy)ethyltridochloride. decylphosphonium chloride.

XVIII XIII 1. 0 Trimethyl phos- 1. 0 Acetic acid, 500 ml. 80 Z-dimethylphosphatoethyltriethylphate, phosphonium chloride.

XXIX XII 1. 0 Propionic acid 2. 4. DMF, 300 ml 10 2-propionyloxycthyltrihexadccylphosphonium chloride.

XXX XIV 1.0 Butanoic anhydride. 1.0 DMF, 1,000 1111-.-- 2-butyryloxyethylbutylethylhcxylphosphonium chloride.

XXXI-- XV 0.8 Acetic acid 4. 0 None 118 2-acet0xyethyldiethyl-2-ethoxyeth 1.

phosphonium chloride.

XXXIL.-. XVI 0. 9 Acetyl chloride. 1. 0 DME, 200 ml 65 2-acet0xyethyltricyclohexylphosphonium bromide.

XXXIII--. 1.0 Hexanoyl chloride. 1. 9 Dioxane, 150 ml--- 25 2-11exanoyloxyethyltricyclopcntyl- V phosphonium chloride. XXXIV- 1. 0 Acetic anhydride- 0 None 100 2-acgiodxyethyltriphcnylphosphonium XXXV- XVIII. 1. l Stearyl chloride--- 3. 3 DME, 700 m1 2-stearyloxyethyldiphenylnaphthylphosphonium iodide.

XXXVI. XX 1.0 Dodecanoyl bro- 4. 0 DMF, 1,000 1111--.. 40 2dodecanoyloxyethyltri(parachloromide. phenyDphosphoniurn chloride.

XXXVII- XXI 1. 0 Phenylsulionyl 1. 0 Dioxane, 600 ml-.- 2-(phenylsulionyloxy)cthyltri(parabromide. I tolyl)phosphoniu1n chloride.

XXXVIII- V 1. 0 Ethylchloroiormate. 2. 0 Diglyme, 300 ml..- 40 2-(ethoxycarbonyloxy)ethyltrimethyl phosphonium bromidc.

XXXIX--. VII 0.9 Dipropyl carbonate. 3. 0 DME, 250 ml- 100 2-(propoxycarbonyloxy)ethyltributylpliosphouium chloride.

L VII 1. 0 Ketene 1. 0 THF, 500 ml 2-acetoxyethyltributylphosphonjum chloride.

8 DMF Dimethyliormamide.

TABLE G G9 9 6B 9 R R R PCH2CH2OY'X+BaSB RRZRSPCHZCHZX Example Product of Base Moles of Solvent milli- Temp., Product No. Example No. RR R PCH2CH2OY-X Base liters (1111.) O.

XLI 1. 0 K1003 1.0 DME, 300 ml- 83 Vinyltrlmethylphosphonium bromide.

XLII 1. O N34CO3 2. 0 Dloxane, 300 ml.-. 100 Vinyltributylphosphonium chloride.

XLIIL 1. 0 LuCO; 4. 0 M 1 51 a cetate, Do.

in XLIV 2. 0 Mg(COa) 8.0 Diglyme Vinyltributylpho5pl1 nium iodide. XLV 0. 5 Ba(OH)z. 1.0 Acetonitrlle, 500 80 Vinyltriisobutylphosm phonium chloride.

XLVI XXVII- 0. 9 CMOH): 1. 1 THF, 600 ml 60 Vinyltridodecylphosphonium chloride.

XLVIL. XXVIII 1. 0 Polymeric trunethyl- 4. 0 DME, 400 ml- 85 Vinyltriethylphosphobenzyl ammonium nium chloride. chloride.

XLVIII- XXIX 1 0 KOH 1. 0 THF Vinyltrihexadecylphosphonium chloride.

XLIX XXX 1 0 NaOH 0 Acetonitnle 20 Vinylbutylethylhexyly phosphonium chloride.

L XXXI l 0 LIOH 1 0 .....d0 60 Vinyldiethyl-Z-ethoxyethylphosphonium chloride.

LI XXXII-. 1.0 Mg(OH)2 3.0 THF 72 Vinyltricyc1ohexy1 hos phonium bromide.

LII XXXIIL--- 2. 0 (33(003) l- 0 Dloxane Vinyltricyclopentyl- 7 phosphonium chloride.

LIII XXXIV- 0. 5 132K003) 1. 0 DME 81 villylttiphenylphosi phonium iodide.

LIV XXXV-. 3. 0 Polymeric trlethyl- 1. 0 Dioxane 97 Vinylphenylnaphthylbenzyl ammonium phosphonium iodide. hydroxide.

LV XXXVI- 1. 0 Polymeric triethyl- 5. 0 DME 50 Viny1tri(para-ch10r benzyl ammonium phenyl) phosphonium hydroxide. chloride.

LVI XXXV II 1. 0 Actlvated alumina l. 0 THE 35 Vinyltri(para-tolyl) phosphonium chloride.

LVII XXXVIII. 1.0 Tetrameihylammonium 1. 7 Diglyme 42 Vinyltrimethylphoshydroxide. phonium bromide.

LVIII XXXIX- 2.0 Tetrapropylammonlum l. 0 DMF 37 Vinyltributylphosphohydroxide. nium chloride.

LIX XL 1.0 Tetrabenzylammomum 1.0 DME 25 Do.

hydroxide.

a When not specified the amount of solvent employed is 500 milliliters.

TABLE I) G) 6 base 63 6 R R R PCHzCHgoH-X R R R PCH=CHg-X Example Product of Temp., Dehydrating 500 Milliliters of No. Exlarmple Base 0. Agent Solvent Product 120 Silica gel Vinyltributylphosphonium chloride. 100 Silica-alumina Vinyltridodecylphosphonium chloride. 220 Vinyltrihexadecylphosphoniurn chloride. 180 Silica-alumina Virfildigthyl-Z-ethoxyethylphosphonium c on e. Mg(OH) 150 Silica gel Vinyltricyclohexylphosphonium bromide. XVIII. N 32003..-. 250 Vinyldiphenylnaphthylphosphonium iodide. X BaCO': 205 Vinyltriphenylphosphonium iodide. XX NazC O3 200 Virgltripara-chlorophenyl)phosphonium c on e. XXI Activated alumina" 175 Vinyltri(para-tolyDphosphonium chloride.

* Finely-divided particulates. b Finely-divided particulates.

TABLE E Example No. R R R P II Temp, C. Solvent Product XCHzOHgOC-CHa Tridodecylphosphine X=Br Reflux Ethanol Tridedecyl-2-acetoxyethylphosphonium bromide. Tricyclohexylphosphme X=I 85 Acetonitrile Tricyclohexyl-Z-acetoxyethylphosphonium iodide. Tris(2-chlorophenyl)phosphme X=Ol Reflux..- Acetone Tris(2-chlorophenyl)-2-acetoxyethylphosphonium chloride. Tris(2-methoxypentyl)phosphine X=I 50 Dioxane 2-acetoxyethylphosphonium iodide.

By finely-divided particles in Table D is intended 28 to 200 mesh. Larger or small particulates are likewise within the purview of the instant discovery.

EXAMPLE LX Tributylvinylphosphonium bromide Tributyl 2 acetoxyethylphosphonium bromide (23.7 millimoles) is dissolved in 1,2-dimethoxyethane milliliters) and sodium carbonate (5.0 grams, 47 millimoles) is added. The mixture is stirred at reflux under nitrogen for 8 hours. The solid is filtered OE and washed with hot, 1,2-dirnethoxyethane. The combined filtrates are evaporated to leave a semi-solid residue. Recrystallization from ethyl acetate yields product tributylvinylphosphonium bromide (3.3 grams, 10.7 millimoles, yield with melting point 148 C.150 0.). Further recrystallization from ethylacetate-acetonitrile raises the melting point to 151.5" C. to 152.5 C.

The products of equations and Tables B, C, D and E hereinabove may be reacted, pursuant to the present invention and according to the reaction conditions of equation (C), supra, with a monohydric alcohol of the formula ROH wherein R represents trialkyl(C -C )silyl-substituted lower alkyl; monoand dilower alkoxy-substituted lower alkyl; lower alkoxy-substituted lower alkoxy-alkyl(lower); phenyl; substituted phenyl; benzyl; and cycloalkyl. The product salt has the formula [R R R %OHQCHgOR]I K wherein R R R and X have the meanings given hereinbefore.

The following examples illustrate this reaction, Examples LXI through LXXI being carried out essentially as in Example LX(a), excepting as shown in Table F:

EXAMPLE LX(a) 2-eth0xyethyltributylphosphonium tetraphenylborate The products of Examples LX(a) through LXXI may be employed as fire retardants in the manner defined hereinabove for the phosphonium salts of equations (B) through (E).

In Table F 500 milliliters of solvent is used in each example.

Clearly, the instant discovery encompasses numerous modifications within the skill of the art. Consequently, while the present invention has been described in detail with respect to specific embodiments thereof, it is not intended that these details be construed as limitations upon the scope of the invention, except insofar as they appear in the appended claims.

What is claimed is:

1. A compound of the formula 061m 0,11,) 0213a) (C2H6) PomomoHc CHzCH OH 21 01 3. The compound 69 Pcrnonzoomomoomomoomwnmcn. m

4. The compound as P CHzCHzO- 1 CH Cl 5. The compound 14 6. A method which comprises bringing into reactive contact a phosphonium salt selected from the group consisting of RIRQRKP ornornoY-xand R RR POH=6Hz'X- and an alcohol of the formula ROH in the presence of a base, and recovering the corresponding salt of the formula wherein R, R and R in the above formulae each represent a member selected from the group consisting of alkyl C -C substituted alkyl (C -C cycloalkyl, and aryl, said substituents for alkyl being selected from the group consisting of lower alkoxy and cyano;

Y is the residue of an esterifying agent;

X is halogen;

R is a member selected from the group consisting of alkyl C C trialkyl(C C )-silyl-substituted lower alkyl, monolower alkoxy-substituted lower alkyl, dilower alkoxy-substituted lower alkyl, lower alkoXy-substituted lower alkoxy-lower alkyl, alkyl(C -C )oXy-lower alkoxy-substituted lower alkyl, phenyl, substituted phenyl, benzyl and cycloalkyl.

7. The process of claim 6 in which reaction is made to take place in an inert organic solvent.

8. The compound [Geo-0. 11031 cntongo CHzS1(GH Cl References Cited UNITED STATES PATENTS 2,514,131 7/1950 Kaszuba 260-6065 2,745,877 5/1956 Bindler et a1. 260-6065 FOREIGN PATENTS 465,200 4/1937 Great Britain.

OTHER REFERENCES Laible, R. 0.: Chemical Abstracts, 53, 1959, page 19975 (b).

Rothstein et al.: Iour. Chem. Soc., London, December 1953, pp. 3994-4004.

TOBIAS E. LEVOW, Primary Examiner.

SAMUEL H. BLECH, W. F. W. BELLAMY,

Assistant Examiners. 

1. A COMPOUND OF THE FORMULA (R1-P(+)(-R2)(-R3)-CH2-CH2-O-R) X(-) WHEREIN R1, R2 AND R3 EACH REPRESENT A MEMBER SELECTED FROM THE GROUP CONSISTING OF ALKYL C1-C16, SUBSTITUTED ALKYL C1-C16, CYCLOALKYL, AND ARYL, SAID SUBSTIUENTS FOR ALKYL BEING SELECTED FROM THE GROUP CONSISTING OF LOWER ALKOXY AND CYANO; R REPRESENTS A MEMBER SELECTED FROM THE GROUP CONSISTING OF TRIALKYL(C1-C8)SILYL-SUBSTITUTED LOWER ALKYL, MONO- LOWER ALKOXY-SUBSTITUTED LOWER ALKYL, DI- LOWER ALKOXY-SUBSTITUTED LOWR ALKYL, LOWR ALKOXYSUBSTITUTED LOWER ALKOXY, ALKYL(C1 TO C8)OXY-LOWER ALKOXY-SUBSTITUTED LOWER ALKYL, PHENYL, SUBSTITUTED PHENYL, BENZYL AND CYCLOALKY; X IS HALOGEN. 